1. Field of the Invention
The present invention relates to a connector.
2. Description of the Related Art
A connector is used to electrically connect a plurality of electronic devices or electronic parts.
The connector can be classified into various types according to its configuration and the like.
For example, based on mount mode, connectors can be divided into a substrate connector that is connected to a substrate, an LSI socket that is connected to an LSI, and a relay connector that is used for connecting a cable to another cable.
Among the different types of connectors mentioned above, the substrate connectors can be further divided into a card edge type connector and a two-piece type connector.
FIGS. 1 and 2 show examples of the card edge type connector used to connect a mother board 1 to a daughter card 2, wherein pads 3 arranged on patterns (not shown) formed at both sides of the daughter card 2 are held between a pair of contacts 4. Thus, in this configuration, the patterns of the daughter card 2 are used as inserting contacts. A connector 5a shown in FIG. 1 is a through hole mount type connector. That is, the connector 5a is mounted to the mother board 1 by inserting one end of each of the contacts 4 through a corresponding through hole (not shown) formed at the mother board 1 and fixing the contacts 4 to the mother board 1 through soldering. On the other hand a connecter 5b shown in FIG. 2 is a surface mount type connector. That is, the connector 5b is mounted to the mother board 1 by fixing one end of each of the contacts 4 to a corresponding pad 6 formed on the mother board 1 through soldering.
FIG. 3 shows an example of the two-piece type connector. In this drawing a connector 5c has two connectors 5c-1 and 5c-2, one being inserting and the other being receiving, and the two connectors are each mounted on different substrates 1 and 7. The connector 5c is used by engaging the two connectors 5c-1 and 5c-2.
As described above, the connector may have various configurations depending on its mount mode and the like; however, the above substrate connector, the LSI socket, and the relay connector all have a housing (corresponding to the parts indicated by numeral 8 in FIGS. 1–3) made of insulating resin that accommodate numerous pin-shaped or tongue-shaped contacts made of metal.
To form a press-fit type pin contact, sheet metal is processed by die cutting, punching, bending, or forming press to produce a number of presswork pin contacts. Also, for fabricating tongue-shaped contacts, sheet metal is die-cut or punched in a similar fashion. Sheet metal is normally used for the contacts so as to obtain spring characteristics. Also, the contact is plated with a base plating and then with gold in order to obtain good conductivity.
Like many electronic parts such as a wiring board and the like, the development of the connector has always been concerned with size reduction and achievement of a higher density (narrower pitch) of the contacts, that is, a larger number of contacts to be implemented in the connector.
However, since the conventional connector has contacts that are pin-shaped, it can be rightly assumed that there is a limit to reducing the size of the connector or increasing the density of the contacts. For example, with regard to the density of the contacts, it is difficult to achieve a pitch that-is lower than 0.2–0.3 mm.
Also, in the conventional two-piece connector, two connectors are used, thereby imposing a further limit on attempts to reduce the size of the connector. Also, in this conventional two-piece connector, there is also a problem of noise being generated at the connecting portion of the two connectors.